Question

Researchers stationed at different areas on a mountain and in a tunnel midway through the mountain boiled water at the same time. Even though the water at every station was at the same temperature, the pot at the top of the mountain started boiling before the others. Why?
Water boils when the vapor pressure is___________ the atmospheric pressure. The atmospheric pressure_________ at the top of the mountain.


choices for blank 1: less than ---greater than----equal to
choices for blank 2: is greatest---is least---equals to standard pressure

Answer 1

Second problem

Let's start with the second question first. If you understand that, the first question is a little easier. By the way, this is an excellent question to get a handle on. Less than and more than can be nightmares in the sciences. Every question that you come across that uses less or more, you should treat with a great deal of care.

As you go up in altitude the air pressure becomes less and less (key word: less print out the sentence underline it in color. Think about it.)

When the pressure decreases, it takes less energy (key word again) to get the water molecules to escape the surface. So the temperature is less than it would be at sea level.

Answer for problem two: Least

Problem One

Water boils when the maximum number of molecules can escape the water's surface. Equal to is the correct answer.  It's hard to find the exact answer to this, but equal to is the correct answer.